fix: ignore target=_blank links

[dummdidumm]

Also some docs on how to know when native confirmation dialog appears fixes #8482

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[Conduitry]

Are there other targets we should also be ignoring? I'm aware of _self and _blank and (I think) _top plus whatever other custom names you want to have if you're using frames. What do we want to have happen when someone uses target='_self'

I know we probably don't want to think too hard about people using frames, but is there another check here we could perform that would cover more cases a little better? (I'm not saying this because I'm already pretty sure there is one. I'm just asking.)

[dummdidumm]

I thought about this very briefly, too. From reading https://developer.mozilla.org/en-US/docs/Web/HTML/Element/a#attr-target it sounds like we should just ignore _self because it's the default, and for _top and _parent we would have to somehow find out if there's window.parent - I'll adjust the code. Better safe than revisit this later.

[Rich-Harris]

Is this logic right? We want to skip beforeNavigate when links open in a new tab, which IIUC means this:

<!-- should skip beforeNavigate -->
<a href="/other" target="_blank">...</a>
<a href="/other" target="other">...</a>

<!-- should NOT skip beforeNavigate -->
<a href="/other" target="_self">...</a>
<a href="/other" target="_top">...</a>
<a href="/other" target="_parent">...</a>

[Rich-Harris]

Actually on a closer read, I think the only change we need is to respect user-defined targets

[dummdidumm]

Oh right, I forgot about those, yeah the if condition needs to be adjusted